A few friends of mine and I were recently talking about Lockdown and his upgradeability. We already saw the Blazing version with his ashtastic chainsaw, but that surely only scrapes the surface of the potential there. And seeing as there are all those talented fan manufacturers, it would definitely be possible to see more weaponry and gimmicks for him, especially with all the wonderful homaging potential.

I second the OP Energon-axe idea, but in terms of less TF-related items (like the "ashtastic" chainsaw), maybe Samus Aran or Mega Man's arm cannon? Or maybe a weapon from Power Rangers, or something like the original Megazord's shoulder plate with the big M on it, as a little homage to/jab at Ban Dai?